A local area network (LAN) can transfer data and messages between computer systems and storage elements through a high-speed network. The LAN consists of a communication infrastructure, which provides physical connections. It also includes a management layer, which organizes the connections, computer systems, and storage elements, so that data transfer is secure and robust. The LAN allows any-to-any connections across the network by using interconnect elements such as switches. The LAN introduces the flexibility of networking to enable one server or many heterogeneous servers to share common communication facilities. A network might include only computer systems, or may additionally include storage devices, including disks, tapes, and optical storage.